This invention pertains to a portable device that provides additional battery power for jump-starting stranded vehicles whose internal battery is discharged.
There are two types of existing products of similar function in the market:
A Booster Cable is a pair of parallel cables. Each end of the cable is attached to one pair of alligator clamps. The clamps are clamped on to the battery terminals so that electric current flows from a boosting battery to the discharged battery. This provides power to start the stranded vehicle.
A Booster Pack is a pair of cable connected at one end to the built-in battery of a portable box while the other end connected to a pair of alligator clamps. When the clamps are connected to a discharged battery, current flows from the built-in booster battery of the booster pack to the discharged battery of the stranded vehicle.
For booster cable sets and booster packs, it is important that user will makes the correct polarity connection between the clamps and the batteries. If the connection is reversed, firing sparks will discharge at the contact points and may cause damage to property or to people.
Traditionally, many inventors attempted to reduce or to eliminate the risk of reverse connections associated to the use of booster cable sets. In U.S. Pat. No. 4,366,430, Wright taught an art using a manual switch and a voltage detector in order to determine whether a connection was safely made. Further, in U.S. Pat. No. 4,420,212, Wright taught another art of using light emitting diodes ("LED") for indication of polarity of connection. Later, McGowan, in U.S. Pat. No. 5,796,255, disclosed another art of using LED art and voltage detection method to indicate and detect correct connection in using booster cable sets. These methods can detect an improper connection. Upon viewing the good connection, the user will press a switch to complete the electric path between the booster battery and the discharged battery.
The inventions require user to make judgment based on viewing the LED indication and then manually activate the switch to complete an electric path between the two batteries. Also, after the booster cable successfully jumped starting the stranded vehicle, the inventions require user to activate switch again to terminate the electric path. If a careless user forgets to press the switch after jump starting a stranded vehicle, the dislodged clamps may discharge firing sparks. The same peril exists when a second connection is made with reverse polarity.
Other inventors have attempted to reduce or to eliminate the spark risk when using booster packs. In U.S. Pat. No. 5,589,282, Roxon disclosed an invention providing a holster to house the permanently charged clamp of the booster pack. In this invention, the holster is permanently attached to the main portable enclosure body of the booster pack unit. In U.S. Pat. No. 5,183,407, Srol invented the use of an insulated cap to protect the charged clamp of the booster pack unit.
In these booster pack inventions, once the user dislodges the clamps from either the holster or the cap, the peril of an improper connection remains.
This invention solves all of the above problems of reverse connections, shorts, spark firing and battery explosion. The solution is provided below in the detailed description.